Method of corrosion inhibition



United States Patent 3,233,963 METHOD OF CORROSION INHIBITION John F. Olin, Kettering, Dayton, Ohio, assignor to Pennsalt Chemicals Corporation, Philadelphia, Pa., a corporation of Pennsylvania No Drawing. Original application June 6,1960, Ser. No. 33,910, new Patent No. 3,139,439, dated June 30, 1964. Divided and this application Nov. 7, 1962, Ser. No.

2 Claims. (Cl. 21-2.7)

This application is a divison of application Serial No. 33,910, filed June 6, 1960, and now Patent No. 3,139,439.

This invention relates to a novel class of heterocyclic compounds, to their preparation, and to their use as oil well bactericides and as agricultural chemicals. More particularly, the novel compounds of this invention have the following chemical structure:

Likewise, it is known from US. Pat. 2,744,898 that a polyhaloolefin (e.g. an alkenyl dihalide) will react with an alkali metal dithiocarbamate to yield the haloalkenyl ester. Thus, sodium dirnethyldithiocarbamate and 1,3- dichloro-Z-butene yield 3-chloro-2-butenyl dimethyldithiocarbamate. It is also known to prepare bialkylene diesters of dithiocarbamates by reaction of two moles of the dithiocarbamate salt with one mole of an alkylene dihalide- Thus, U.S. Pat. 2,384,577 shows the preparation of methylene bis(dimethyldithiocarbamate) by reaction of methylene dichloride with sodium dimethyldithiocarbarnate. This patent also discloses that instead of using methylenejdichloride, other acyclic dihaloalkanes may be employed to give similar diesters such as ethylene. dichloride, ethylenedibromide, trirnethylene dibromide, and the like although no examples are given my confirm this prediction.

I It has now been unexpectedly found, however, that when alkali metal dithiocarbamates are reacted with cer-. tain alkylene dihalides in accordance with this invention, simple ester formation does not occur, but a novel class of compounds is obtained. Now, according to this invention, the novel heterocyclic compounds above defined where X- is Br are obtained by reacting an alkali metal salt of a dithiocarbamate with a stoichiometric excess of an ethylene dihalide having the structure where R is selected from the group of hydrogen, alkyl, cycloalkyl, haloalkyl, and aryl radicals and X is a halogen atom selected from the group of bromine and chlorinc atoms.

To prepare these novel bromides it is preferred to add a solution of the dithiocarbamate salt, preferably an aqueous, an alcoholic, or an aqueous-alcoholic solution of the dithiocarbamate, to a stirred solution of the dihalide in a solvent such as an alcohol or aromatic hydrocarbon (e.g. benzene). By adding the dithiocarbamate to the dihalide an excess of dihalide is always present. The process is exothermic and is triggered by mild heating of the dihalide solution to about 50 to 90 C. The

products are isolated readily in the usual manner by crystallization, by evaporation of the solvent medium, by extraction, or by combinations of these techniques.

The alkali metal dithiocarbamate reactants are well known compounds prepared by reaction of carbon disulfide with the appropriate amine in an aqueous alkali metal hydroxide solution. The dithiocarbamates may be derived from any of a wide variety of secondary monoand polyamines such as N,N-di-alkyl amines, N-alkyl-N- cycloalkyl amines, N,N-dicycloalkyl amines, N,N diaralkyl amines, N-alkyl-N-aralkyl amines, N,N-dialkylalkylene diamines, N,N-dialkyl dialkylene triamines, and the like. Some specific amines which exemplify these classes are dimethylamine, ethyl methylamine,

methylcyclohexylamine, dibutylamine, dicyclohexylathe like.

, methylene dihalides and 1,3-dihalides give esters.

mine, di-n-octylamine, didodecylamine, dibenzylamine, benzyl-methylamine, N,N-diethyl 1,6 hexanediamine, N,N-dimethyl-1,4-butanediamine, N,N dimethyl ethylene diamine, N,N"-dimethyl-diethylene triamine, and Preferably, the dithiocarbamates used will be N,N-dialkyldithiocarbamates containing from one to about twelve carbon atoms in each alkyl radical. It will be understood that mixtures of amines may be reacted with the carbon disulfide and the mixture of dithiocarbamates thus formed reacted with the dihalide to produce mixtures of products.

The ethylene dihalides having the above defined structure are also readily available compounds. It will be observed that dichlorides are excluded from the above structure since the compounds with structures like those of this invention are not obtained when dichlorides are used. Thus the dihalides operable include dibromides and bromo-chlorides as defined by the structural formula. The dihalides, as indicated, must be 1,2-dihalides since However, because the R groups may be selected from any of a wide variety of radicals, the 1,2-dihalides which may be used are large in number. As 'mdicated, the R radicals may be hydrogen, alkyl, cycloalkyl, haloalkyl, and aryl radicals and they may be the same or different. In order to avoid low reaction rates due to steric hindrance, however, it is preferred that not all the R radicals of the dihalide used be bulky radicals (cg. phenyl or naphthyl). Preferably, 1,2-dihalides will be used in Y which at least two R radicals are hydrogen atoms. Specific examples of the dihalides which may be used include l-bromo-Z-chloroethane, 1,2-dibromoethane, 1,2,3- tribromopropane, 1,2-dibromo-3-chloropropane, 1,2 dibromo-l-phenylethane, 1,2-dibromo-n hexane, 1,2 dibromo-n-octane, 1,2-dibromo-l-cyclohexylethane, 1,2-dibromo-1 ,2-diethylethane (i.e., 3,4-dibromo-n-hexane), 1- bromo-Z-chloro-1,2-diphenylethane, 1,2-dibromo-eicosane, 1,Z-dibromo-l-naphthylethane, and the like. Preferably, the dihalides will be those where R is hydrogen or where at least two R radicals are hydrogen and the remaining Ba a...

where R and R are defined above. When the dithi'ocarbamate is derived from an alkylene diamine, the value of x is one and the integer n corresponds to the number of methylene groups in the diamine chain. Thus, one mole of the bis-dithiocarbamate from N,N'-diethyl-l,4-

butanediamine reacts with two moles of 1,2-dibromoe-.

25rs s s s tain. tHHtH.

When the dithiocarbamate is polydithiocarbamate derived from a polyalkylene polyamine the value of x is greater than one.

ane the compound obtained is As indicated, the process. of this invention yields the novel compounds Where X is a bromide ion. However,

these bromides are readily converted to other halide salts. Thus the bromide is converted to the or hydroxides. chloride compound by blowing air through an aqueous solution of the bromide containing HCl and a small amount of HNO In this way the bromide ion is .oxi-

dized to Br which is volatilized from the system leavingthe chloride which is readily isolated. The same technique can be used to obtain the fluoride salt using HF instead of HCl.

used to convert quaternary halides to hydroxides.

The lower molecular weight members of this novel Thus, with the tri-dithiocarbamate from. N,N"-dimethyl-diethylenetriamine and 3,4-dibromohex- The hydroxide is readily obtained by reacting silveroxide with the bromide salt in the manner.

. 4 of the agent may be injected batchwise or continuously in the well ttubing-casingannular space. The concentration of agent in the aqueous solution will usually be from about 5 to 50 p.p.m.

The following examples will further illustrate the preparation and use of the novel compounds of this invention.

EXAMPLEAI r A solution of 225 g. (1.551rn.) of ethylenechloro: bromide. in 100 guofmethanol is placed in a flask fitted with a mechanical stirrer. Then an aqueous solution containing 439 g. (l .m.) of sodium dibutyldithiocarbamate is added dropwise.

50 C. by external cooling. When the addition is com- Plete the aqueous solution is evaporated under vacuum to a volume of about-400 cc. and 1 liter of isopropanol is added and the solid NaCl which precipitates'fromsolunight.

tion is filtered ofi. Then, 500 cc. of. benzene is added to the filtrate and the solution is evaporated under-vacuum to 400 cc. volume. Then, 500 cc. of toluene is added and the vacuum distillationis continued, another 1000 cc. of toluene being added during the distillation to remove all the water. When the water is entirely removed, crystallization beginsand the mass is held refrigerated over- The crystals are then filtered 01f, driedat 70 0.;

the weight of dried-crystalsbeing 328 g. The dry, white crystals melt-at 120 to 122 C. They are soluble in water, ethanol, and hot acetone, but insoluble in cold acetone, benzene andhexane. A test for bromide ion on the aqueous solution of the compound is found to be positive. the structure is designated as follows:

5 Aimlysis:-:Founc l/theory: Percent C,42.28/42.3; percent H, 7.13/7.10; percent N, 4.47/4.48; percent S, 2056/ 20.53;. percent Br, 25.63/2559.

EXAMPLE 1 2 A solution of 287 'g. (2 m.) of ethylenechlorobromide in 300 g. of methanol is, placed in afiask fitted-with a mechanical stirrer. and the solution is heated to- C.

class of heterocyclic compounds are colorless, crystalline solids, soluble in water, and have sharply defined melting points. As the molecular Weight increases above about 350 the compounds become oils or waxy solids. Where the compounds have a long chain substituent they are effective surfactants by virtue of their combined ionic (hydr'ophylic) and oleophylic character.

These com- I pounds also have antimicrobial and disinfectant'activity as expected from their similarity to quaternary ammonium halides.

in oil wells (genus Desulfovibrio) which cause corrosion 70 and deterioration of submerged metal installations. When used for this latter purpose it is merely required Those compounds wherein R is a lower alkyl 3 group (i.e., from one to four carbon atoms) are useful as insecticides, being particularly effective on mites and that the agent be incorporated in an aqueous drilling mud i or a separate treatment of the well may be made by flushing an aqueous solution of the compound through thesystem. In still another technique an aqueous solution Then' as the solution is stirreda 40% by weight aqueous solution of dimethyldithiocarbamate containing 714 g. (2 m.) of sodium dimethyldithiocarbamate is added dropwise over a one-hour period, cooling as necessary to maintain the temperature at about 601 C. The reaction mass is then allowed to stand 48 hours after which it is twice extracted'w'ith 200 cc. of toluene, and theextract evaporated until virtually dry. The. resulting oil and salt residue is taken up in about 600 cc. of warm butanol and filtered to remove the NaCl. To the. filtrateis then added a liter of toluene and the solution cooled, after which a large crop. of crystals is obtained. These are filtered, suckeddry, and are dried in an oven at 65 C. thus obtaining 370 gof'colorless crystals melting at l66-168 C. The product which has the structure I dea -(EH,-

is soluble in water, alcohol, and slightly soluble in toluene. It Is msoluble in hexane and acetone.

A l 1alysis:- Found/theory: Percent Br, 34.2/ 35.7; percent S, 27.6/ 28..

g A mild exothermic reaction occurs. and the temperature of the reaction mass is held at about Based on this and the analysis of the compound,

EXAMPLE 3 A solution of 40.5 g. of 98% sodium hydroxide in 350 been completely added. Excess carbon disulfide is 'removed from the reaction mass by warming and applying slight vacuum.

A solution of .160 g. of ethylenechlorobromide in 100 g. of methanol is placed in a flask equipped with mechanical stirrer and the above dithiocarbamate solution is slowly added. A mild exothermic reaction is observed, the temperature rising to 60 C. where it is held during the reaction period. When the addition of the dithiocarbamate solution is completed the reaction mass is stirred at 60 C. for another half hour and the reaction mass filtered to remove the sodium chloride which had formed. The filtrate is partially distilled under reduced pressure on a water bath and the residue obtained is dissolved in 400 cc. of benzene and filtered to remove some additional salt which separates. The filtrate is again evaporated to dryness yielding 427 g. of clear syrup which is dissolved in 50% aqueous methanol and that solution is extracted with ligroin. The methanol solution is then evaporated to dryness on a water bath under vacuum and on standing overnight in the ice box it turns to a waxy solid which liquefies at about 15 C.

The product is assigned the following structure:

dithiocarbamate is prepared and reacted with ethylene chlorobromide. The product has the structure:

and is a pale yellow oil which solidifies on standing and melts at about 28 C.

EXAMPLE 5 Following the details of Example 2, sodium dimethyldithiocarbamate solution is added to a methanol solution of 1,2,3-tribromopropane. The reaction mass is then vacuum distilled, the residue is taken up with water which is again vacuum distilled 01f, and the residue extracted with warm methanol. The methanol solution is evaporated to dryness on a water bath under vacuum and taken up in a small amount of hot water and the solution is placed in a refrigerator. The crystals which form are filtered off, washed with a small amount of cold water and oven dried. The product which is assigned thestructure:

is soluble in chloroform, ethanol and water and insoluble in most other solvents. The crystalline product decomposes at 250 C.

EXAMPLE 6 A solution of 240 g. of 1,2-dibromoethylbenzene (0.91 mole) is g. of benzene is heated to 60 C. and 529 g. (0.91 mole) of a methanolic sodium dibutyldithiocarbamate solution is slowly added over one half hour period. The salt is filtered 0E and the filtrate distilled on a water bath. Upon taking up the residue with hot acetone and filtering, the filtrate upon evaporation to dryness yields a viscous amber colored oil which is confirmed by bromine analysis to be EXAMPLE 7 N,N-dibenzyldithiocarbamate sodium salt is prepared from dibenzyl amine and carbon disulfide in an aqueous butanol solution containing caustic. This dithiocarbamate solution (1 mol) is added to a solution of 157 g. (1.1 mol) of ethylenechlorobromide in 100 g. of butanol heated to 60 C. The reaction mass is evaporated under vacuum and is extracted with an aqueous methanol solution from which is obtained pale yellow crystals melting at 164 to 165 C. These crystals are soluble in water and ethanol, insoluble in acetone and benzene. The compound is assigned the structure o S S EXAMPLE 8 To a solution of 240 g. (0.88 mol) of 1,2-dibromooctane in 200 cc. of isopropanol there is slowly added with stirring and at 80 C., 480 g. of a 30.6% aqueous solution of sodium diethyldithiocarbamate. The reaction product contains a small amount of yellow oil which is removed by extraction with several portions ofv carbon tetrachloride. The aqueous alcoholic reaction mass is then evaporated to dryness under vacuum, and the residue is taken up with cc. of butanol and 200 cc. of acetone from which was filtered 01f the sodium bromide salt which had formed. The filtrate is evaporated under Vacuum, and the light yellow residual oil is taken up with 250 cc. of acetone and again evaporated to dryness under vacuum. The pale amber syrup which is obtained is assigned the structure i Y Analysis.Found/theory: percent Br, 239/235; percent S, 18.3/18.8.

7 EXAMPLE 9 Following the details of Example 3, 1,2-dibromododecane is reacted with sodium diethyldithiocarbamate to yield an oil of structure o r r CH2-CH Analysis.F.ound/the ory: percent br, 19/ 20.2.

EXAMPLE 10 An excess of carbon disulfide is slowly added to an aqueous caustic solution of N,N-diethyl-ethylenediamine in order to prepare the corresponding dithiocarbamate. A slurry oi'this dithio'carbamate is then added to an alcoholic solution of ethylenec'hlorobromide at reflux .and a mild exothermic reaction is observed to occur. After the addition is complete the mixture is refluxed for an additional 15 minutes and then most of the alcohol is distilled oh" and the aqueous solution extracted three times with chloroform. The aqueous portion of the extract 2 is evaporated to dryness and the water is removed by repeated distillations with a mixture of pent-anols, with isopropanol, and finally with a mixture of isopropanol and benzene. ,After standing overnight the residue ob tained is partly crystalline. Toluene is then added and the mixture is cooled to -15 C. The crystals thus obtained are filtered oil and Washed with acetone 'con-, taining a little methanol. Thevery deliquescent crystals are taken up in hot isopropanol, filtered, and the crystals again taken up in benzene andrthe mass 'azeotropically 3 dehydrated. The residue is cooled to 'l5-" C. and the crystalline. solid obtained is filtered oil and Washed with isopropanol and dried. The white crystals melt at 2 03- 208 C. with decomposition; Analysis as shown below confirms the following structure:

(lie-5H.

Analysis.Found/theory: percent N, 5.2/5.8; percent S, 25.0/26.7.

EXAMPLE 11.USE AS 'PLANT DEFOLIANT An aqueous dispersion of 0.2% by Weight of the. test compound is prepared and applied to mature cotton plants at a rate of 125, gallons per acre. The nurn berof.

leaves per plant is determined before the application and 5 two weeks after treatment. The results are expressed as percent of leaves defoliated.

When the compound of Example 3 is evaluated bythis test, 100% defoliation is obtained and with 616 601111 pound of Example 4, 73% defoliation is achieved. 0

EXAMPLE 12.USE AS OIL WELL BACTERIC DE AND CORROSION INHlBITOR A. Corrosion inhibition of oilfield water Standard corrosion test steel coupons are placed in airtight bottles which are thenfililed'completely with a corrosive oilfield Water to which is added fixedquantities of the inhibitor to be tested. The bottle is then closed and attached to a Wooden wheel that is rotated at a con-. stant speed of 20 rpm. by an electric motor for a period of 72 hours. The coupon is of such size that it will move up and down freely in the bottle filled with the corrosive liquid as the wheel rotates. Thus the coupon will move approximately 86,400 times during the progress of the test.

The bottles are sealed carefully so that the tests are run in oxygen-free medium. The; tests are carried .on in.

an air conditioned room at an average temperature of 72 F.

Before being'plaeed in the bottle the steel-coupon is weighed carefully. Atthe end of the test the cou-pons condition is observed, it iscleaned, and then reweighed, and the 'lossflin Weight, as a result of corrosion recorded.

The loss'in weight is converted into standard corrosion terminology of IPY and MPY by the following equation:

. 24X365Xw IPY (2.5%D XAXSXt where IPY.'='inc'hes. per year '24=number of hours in day 365=daysin year w=weig ht lossof sample :in grams 2.54'cm.==1 inch A.='are'a in sq. in.

S .-sp.: gr. of steel coupon t.=tirne in hours I MPY is. 1,000 times IPY.

The percent efli'ciency of the inhibitor is calculated as follows:

IPY of Control-I P Ywith Inhibitor Percent IPY of Control These equations are standard for reporting results of corrosion tests.

The water used in the tests reportedherein is a 50-50 mixture of supply water ,fromthe-Mississippi Lime and of produced water from the Bartlesville sand obtained. from the Russell lease of Don George,.C hanute Field,"

Neosho County, Kansas 'Ilhesewaters are extremely corrosive andmust be. treated to prevent the; destruction of steel equipment with which they come in contact. The supply water as produced contains appreciable quantities of hydrogen sulfide, mostoi wh-ichiis lost by release oi pressure.

In order to simnla-vte field conditions i the Water is antiy arged wi htfizS in the laborat y for the p rpose of the corrosion tests.

RESULTS OF TESTS In the tests the coupons-are immersed in 220 cc. of the mixed water to which is added 42 ppm. H 8. The test Bactericidal effects The compound of 'Ex'aniple 3 is evaluated for potency against Desulfovibrio desulfuricans occurring in oil Well. .water from West Texas. In a control test withoutthe additive 114.1 colonies of the bacteria per milliliter are counted after three weeks incubation-according to a standard test.=. With 5 parts permil-lion of the compound of Example 3 the count is 1.4 colonies per milliliter and no colonies at 10 ppm.

It Will be apparent to the skilled art Worker, that many changes may be made from the above description of this invention Without departing from its spirit and scope and such variations are to he considered as within the purview of the invention.

9 10 I claim: Where R is an alkyl radical containing from six to twelve 1. A method for protecting submerged metal installacar bou, atoms. tions against adverse bacterial and corrosive efiects which 2. The process of claim 1 where R is an oetyl radical. comprises introducing into said submerged installation a compound defined by the structure 5 References Cited by the Examiner R I? R UNITED STATES PATENTS f 2,547,724 4/1951 Sundholm 260-327 Br 2,574,576 11/ 195-1 Marsh v 2125 s 3 3,082,229 3/1963 Nash 260327 Hg-JJH; MORRIS O. WOLK, Primary Examiner. 

1. A METHOD FOR PROTECTING SUBMERGED METAL INSTALLATIONS AGAINST ADVERSE BACTERIAL AND CORROSIVE EFFECTS WHICH COMPRISES INTRODUCING INTO SAID SUBMERGED INSTALLATION A COMPOUND DEFINED BY THE STRUCTURE 